1. Field
The disclosure relates to developing new systems and methods of security, including copy protection for removable media players.
2. General Background and State of the Art
A virtual machine (VM) is a term used to describe software that acts as an interface between compiler code and the microprocessor (or “hardware platform”) that actually performs the program's instructions. A compiler is a special program that processes statements written in a particular programming language and turns them into binary machine language or “code” that a computer's processor uses. Like a real computing machine, the virtual machine has an instruction set and manipulates various memory areas at run time. It is reasonably common to implement a programming language using a virtual machine; the best-known virtual machine may be the P-Code machine of UCSD Pascal. Also, a virtual machine may describe either an operating system or any program that runs in a computer.
Sun Microsystems, developers of the JAVA programming language and runtime environment, is well known for their development of the JAVA Virtual Machine. A JAVA virtual machine interprets compiled JAVA binary code (called byte code) for a computer's processor (or “hardware platform”) so that it can perform a JAVA program's instructions.
JAVA was designed to allow application programs to be built that could be run on any platform without having to be rewritten or recompiled by the programmer for each separate platform. Once a JAVA virtual machine has been provided for a platform, any JAVA program can run on that platform. A JAVA virtual machine makes this possible because it is aware of the specific instruction lengths and other particularities of the platform.
There has been a long felt need to develop improved methods of copy protection in next generation media players, such as a DVD or CD player.
One known content security system used for DVD's is the Content Scramble System (CSS) whereby the data on a DVD is encrypted. The DVD player then decrypts the data as it reads the disc using a 40 bit decryption key. A fatal flaw of CSS, however, proved to be that its keys and algorithms were static. The encryption algorithm was reverse engineered, and every possible decryption key that would play existing DVD discs was made available. Once the secret escaped, the system was forever compromised since there was no way to renew the security algorithms or keys. There are now many programs available to consumers which remove all security from DVD content with a single “click”.
Content owners do not want this to happen again, especially as the fidelity of the content increases. The next content security system should therefore not be vulnerable in this way.
Software vendors have also faced their share of piracy, but given the nature of computers, they have taken a different approach than that used in the entertainment industry for DVDs. Historically, packaged software program (i.e. computer games) manufacturers have protected their content with “procedural security”. That is, there is no static pre-defined method for securing programs, instead each software producer writes or procures a “security code” to secure their content. This procedural security code varies in complexity and technique on a program by program basis, but most importantly, since each program has a different security software implementation, it is not possible to write a general purpose ‘remove security’ program, like those written to circumvent DVD security.
Another known method of copy protection is writing hardware specific instructions. The problem with such a method is that this is extremely limiting. With this method, a different set of instructions must be rendered for each hardware configuration. This is somewhat impractical.
Therefore, a system and a method of providing copy protection to hardware such as media players, that is not hardware specific, is desired. Furthermore, a system and a method of providing robust security, to prevent unauthorized duplication of the media is desired.